The present invention relates generally to accelerometers and, more particularly, to a MEMS-based micro sensor implementation for a tunneling accelerometer with differential sensing useful for seismic activity monitoring.
There is a great interest in monitoring seismic activity of fractured wells in the oil and gas industry. Oil and gas wells typically range in depth from about 2,000 ft, to 20,000 ft. Shallow wells, typically less than 7,000 ft. in depth, generally can be monitored with geophones. Current state of the art geophones are deficient, however, mostly at greater depths due to a need for greater sensor sensitivity for sensing activity in deep wells that is swamped by large seismic activity at shallower depths. As a result, seismic monitoring is needed that is designed to suppress very large seismic activities at the surface and shallow depths such that maximum sensitivity can be obtained for small signals propagated from deep seismic activities.
Embodiments of the present disclosure and their advantages are best understood by referring to the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in one or more of the figures, in which the showings therein are for purposes of illustrating the embodiments and not for purposes of limiting them.